DES MOINES, Iowa (AP) — A sudden and intense snowstorm caused some school bus trips in the Des Moines school district to stretch on for hours.

The snow and winds gusting to 50 mph roared through central Iowa on Thursday afternoon and caught many people by surprise.

School district spokesman Phil Roeder tells The Des Moines Register (http://dmreg.co/1b7R26W ) the buses began their routes just as the worst of the storm hit the area.

One bus that left Greenwood Elementary at 4:30 p.m. was still dropping off students at their homes at 9 p.m. And a bus that left Windsor Elementary at 4:30 p.m. didn’t finish its route until four hours later.

Roeder says bus drivers kept in touch with dispatchers, who tried to reach parents. He noted that not every parent could be contacted.